Excellent point. What's interesting about it is that a stock price contains all sorts of assumptions and information and blends it all together into one number

Excellent point. What's interesting about it is that a stock price contains all sorts of assumptions and information and blends it all together into one number, which is simply the last price that a share traded at based on supply and demand. Surely Goldman has baked a lot of assumptions about market expectations into this assessment, and surely Goldman is wrong about many of those assumptions and right about others. A more nuanced analysis would be a probability distribution of possible price bands at various future dates. Surely by Goldman's logic it is irrational to buy (or perhaps even to hold) Tesla stock at above $185. But Goldman's analysis would also likely have discouraged investment in many other successful firms over the years. One doesn't listen to Goldman because the advice is true, one listens to it simply to reduce the probability of major deviations from the mean across a portfolio.